This reduces the number of external services that must be running to
succesful run 'cargo test'. In this case one the requirements that
ChirpStack has must be present and there is no need to run local
Kafka and RabbitMQ instances.
These integrations can still be tested using the 'test-all-integrations'
feature flag (which is included in the CI workflow).
With the update to diesel 2.0.0-rc0, it is now possible to cross-compile
without emulation. Note that during each (cross)compile, we have to
install libpq-dev for the target platform, as only one version can be
installed at a time (e.g. libpq-dev:amd64 conflicts with libpq-dev:armhf).
